One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,5)(7,8)(9,10)(11,18)(12,17)(13,20)(14,19)(15,21)(16,22)(23,24)(25,26,29,32)(27,30,35,39)(28,31,36,40)(33,37,34,38)(2,5)(6,8)(9,11,14,12,15,23,13,22)(10,16,20,24,21,17,19,18)(25,27)(26,30)(28,33)(29,35)(31,37)(32,39)(34,36)(38,40)(1,3,4,7)(2,6,5,8)(9,11,14,12,15,23,13,22)(10,17,20,18,21,16,19,24)(27,33)(28,36)(30,37)(31,40)(34,35)(38,39)(2,5)(6,8)(9,12,14,23,15,22,13,11)(10,18,20,16,21,24,19,17)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.